"I imagine that most users dramatically prefer the sharing, backup, and organization capabilities of proprietary cloud apps to local files."

My mother has burned family photos to optical disk 20 years ago, we have physical photos that lasted generations. Tell me which app or cloud product I can trust with data for my grandchildren?

Which app will not dissapear, be discontinued, ban you or delete my data if I stop paying?

I uploaded my medical records to microsoft health, now it's all gone.

Paying with credit is convenient, voting in demagogues and populaists is convenient, blind patriotism is convenient, signing contract without reading is convenient, but they all have consequences.

I agree with sentiment but the last time someone handed us a optical disk with memories in it we had to ask a relative for a device they had in the basement for us to read that disk.

Okay but you didn't address their point you just made a think of the children argument. It doesn't change the fact that most people use and prefer, google photos, amazon photos icloud etc. You're one person.

"In May 2017, Google announced that Google Photos has over 500 million users, who upload over 1.2 billion photos every day."

Do they actually prefer it? I am talking about my elderly mother as an example here. People are becoming increasingly more aware of the issue.

Also many phones come woth google photoes preinstalled and enabled by default, I am counted towards that statistic because it uploaded a few things before I disabled it. Even if they really use it, I am betting most of them Also use store same photos as normal files.

I would like to see fresh numbers now that you have to pay for google photos.

It doesn't sound like you're actually disagreeing with what you quoted, but you don't think it's in people's best interest. You may be right!

As an aside, you may want to back up your mother's optical discs; apparently those are starting to fail.